High thermal conductivity conjugated polymers

Maxwell Walde, Paul Braun, and David G. Cahill

NSF ERC – POETS, EEC 14-49548

Molecular dynamics calculations predict thermal conductivities on the order of 50 W/m-K in highly oriented conjugated polymers such as polythiophene and poly(para-phenylene).  Experimental values are, however, more than order of magnitude below the prediction, for reasons that are not known.  As a first step to understand and then exploit the potential high thermal conductivity of conjugated polymers, we are performing thermal conductivity benchmarking on commercially available conjugated polymers.  Via this evaluation, we will determine if conjugated polymers with thermal conductivities on the order of 5 W/m-K (a factor of 10 greater than conventional engineering polymers, yet a factor of 10 below calculated) are easily obtained.  This benchmarking set of investigations will lay the groundwork for a systematic study of conjugated polymers and their variants to gain new physical insights and attempt to bridge the gap between the modest thermal conductivity observed in experiment and the high thermal conductivities predicted by theory.